Hardening Off & Moving Hosta Seedlings Outdoors

Transitioning Hosta seedlings from indoors to the garden.

By Joshua Spece
Last revised January 22, 2008

Growing Hosta seedlings is a great way to help pass the cold winter months. By the time spring arrives, though, the seedlings may start testing your patience as you itch to get back out into the garden among their parents.

By the time the low temperatures remain in the 50's, Hosta seedlings can safely migrate outdoors. If you move them out when the nights still dip below 50 degrees Fahrenheit, you risk shocking the seedlings into a temporary state of suspended animation. Not to worry if this happens. The seedlings will begin growing again when they are ready.

Also be aware of the sun light the tender Hosta seedlings are exposed to. Even if your seedlings were grown under high intensity discharge lights, they can easily burn outdoors. To help them adjust, first move the seedling to a protected area that is heavily shaded. Over the course of a few weeks, you can move them into brighter light. If the seedlings do burn, keep them well watered and they will grow a new flush of leaves within a couple weeks.

The First Winter

The first winter outdoors is an endurance test for your young Hosta hybrids. The weakest may not survive, which is good. We already have enough poor growers in the Hosta world.

Before winter arrives, you will need to decide how you will over winter your Hosta seedlings. With proper care or in areas with mild winters, the seedlings can be left in pots. Most hybridizers plant their seedling in the ground and often have designated seedling beds.

It is a good idea to get the seedlings into the ground well before the first frost. Frost heave can be a problem for plants that aren't able to send roots firmly into the ground before it freezes. A light mulch will reduce the risk of frost heave and help the young plants through the first winter.

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• Introduction to Hybridizing Hostas
• Selecting Parent Plants
  Goals, Fertility, Bloom Period
• Hosta Genetics
• The Mechanics of Hybridizing Hostas
  Flower Anatomy, Preparing & Protecting Flowers
  Collecting & Storing Pollen, Transfering Pollen, Marking Crosses, Keeping Records
• Hosta Seeds
  Harvesting, Cleaning, Storing
• Starting Hosta Seeds
  Planting Containers, Planting Medium, Moisture, Heat, Germination Time
• Growing Hosta Seedlings
  Light Type, Photoperiod, Reflecting Light, Water, Fertilizer, Re-potting
• Problems Encountered While Growing Hosta Seedlings
  Damping Off, Fungus Gnats
• Hardening Off & Moving Seedlings Outdoors
• Culling and Selecting Hosta Seedlings
• Hybridizing Resources